My guess is log files are being written to it? Might want to install a proper drive internally and redirect log storage. With less activity the USB drive should not heat up anywhere near as much.
If you have docker containers and other stuff all on that USB drive I'd really reccomend getting it all off that USB (not just logging) and onto a proper drive of some kind. USB thumb sticks are not reliable long term storage, you will wake up to find the drive failing one day and good chance you lose everything on it with little to no warning.
Another option would be to redirect logs to a ramdisk. That's what I'm doing on a RPI to try to minimize writes on the sd card. The biggest downside is that you lose your logs when you power off the device, but if the alternative is not having logs at all, I think it's still a better option.
Of course, installing a proper drive is still the best solution.